This is mistaking wine snobbery and what sommeliers do. Of course taste is subjective. The primary function of a sommelier is to choose wines from their selections that the people will enjoy based on their tastes (while providing perceived value and yaddayaddasalesman bullshit). I sell plenty of wine I don't like. Outside of some Sancerres, I don't really enjoy Savingnon blanc. I still sell a ton of it. I don't like over-oaked California Chardonnays, but I'll gladly sell a $100 bottle of Chateau Montelana to anyone who thinks they'll enjoy it.
I don't consider myself much of a wine snob though- I routinely drink cheap stuff; I just know what kind of cheap stuff I'm more likely to enjoy.
But in a blind tasting, I can tell the difference between a pinot noir and cabernet or a French wine from an American wine fairly easily if they're produced in traditional ways. Hell, I can usually tell if the oak a wine has been aged in American or French because (if the oak is new) they impart different characteristics.
I drink box wine and I don't care where it comes from
Most are trash, but if you see Bota boxed wine, they're pretty good.
They moved from glass bottles to boxes to be ecologically friendly. You're getting a nice, drinkable wine at cooking wine prices with their stuff. I've poured it for people who didn't know it was from a box and they really enjoyed it.